In last year's Team Safari match in Logan, NM, both members of the JP team shot JP 224 Valkyrie ARs. They placed well in the match. Understand that in this match the team generally has a precision rifle shooter and a AR-15 (or AR-10) shooter.

We had the opportunity to shoot the JP Valkyrie rifles after the match, but it was so late after the awards ceremony that we just wanted to go home.

Originally posted by Il Cattivo:Beyond punching paper and ringing steel, is there really all that much advantage to going from a 75 grain .224" bullet to a 90 grain .224" bullet, even with at Valkyrie's velocities?

IMO Hornady's 73 grain ELD-M makes a better load than their 75 grain HPBT -- the 73 launches a little faster and has better BC. I get 2800 fps MV with my 20" barrel and a can.

The JP guys said they were getting 2650 fps MV for the Valkyrie. I don't recall is they had a 20" or 22" barrel, but it may have been 22". IIRC about 2700 fps is max I've heard for that Federal load, probably with a 24" barrel.

So the Hornady bullet starts out a little faster, flies a little flatter, and drifts a little more in crosswinds. There is a noticeable difference in wind drift once you get targets past 600 yards.

In tactical matches, we rarely see carbine targets past 650 yards, although in last year's team match in Douglass, WY there was one mandatory W..T..F at something like 850 to 900 yards. I took a couple of pokes at it, kicked up some dust nearby to prove I engaged the target, and thus avoid a procedural penalty. Most carbine guys didn't even have dope out that far -- even some of the AR-10 shooters.

Like the other cartridges with larger cases (Nosler 22, 6.8 SPC, 6.5 Grendel), there's more muzzle energy in the Valkyrie. I calculated it at 1400 ft lbs for the Valkyrie versus 1250 ft lbs for my 73 ELD load. For paper punching this means nothing. For ringing steel, the extra energy might help the spotter confirm a hit. For plate sizes set for 6.5mm and such cartridges, a 223 bullet doesn't move the steel much, doesn't produce much splash, and doesn't produce a very loud ring.

From a hunting standpoint, the extra 150 ft lbs at the muzzle is a good thing. However, one shouldn't be hunting other than varmints with 90 SMK or 73 ELD-M bullets. There are other bullets that are better when terminal ballistics count.

If you are receiving this email, it means your current order for one of our JP Supermatch™ barrels in .224 Valkyrie is eligible for fullfilment in our first production run. But, because of the unforeseen complications of developing barrels for a brand new caliber like this, we wanted to contact you before completing your order.

After final testing of these barrels, we have discovered that accuracy specific to 90gr. Sierra Match King and the 90gr. Fusion hunting ammo is only mediocre. These results are not up to the JP standard, and as such, we cannot honor our accuracy guarantee with this 90gr. ammunition.

However, the Federal varmint load using the 60gr. Nosler Ballistic Tip and our personal test loads using 77gr. Sierra Tipped Match Kings shot well from these barrels. With the 77gr. Tipped Match Kings, we achieved maximum velocities in the 3000 ft/s range. This compromise of utilizing lighter projectiles with much higher MV and slightly lower BC may actually result in higher hit probabilities within the effective range of the cartridge. This is particularly the case with unknown distance targets.

At this point, we want to offer you the choice of confirming your order and receiving one of these first JP .224 Valkyrie barrels. Alternately, you may opt to wait for our next run of barrels with further design changes to improve the performance of the 90gr. bullets. The choice comes down to your choice of application and ammo.

Please respond to this email with your preference.

If you choose to wait, your order will still be fulfilled in the order it was received as soon as the new barrels arrive and are tested. If you choose to wait, we expect to ship your order sometime in May.

swage -- did you order one of the JP barrels and receive the above notice?

I wonder if barrel twist rate has anything to do with the issue. I don't know if a 1:7 twist works for those 90 grain bullets; instinct tells me something a little faster might be better. Chamber dimensions might also come into play.

Originally posted by fritz:I wonder if barrel twist rate has anything to do with the issue. I don't know if a 1:7 twist works for those 90 grain bullets; instinct tells me something a little faster might be better.

Bryan Litz has stability data on the 90 grain SMK that he calls “Stability Factor.” Best case conditions are higher altitude, humidity, and temperature; nominal are average temperature, humidity, and sea level; worst case are low temp, low humidity, and sea level. According to him a stability factor of 1.4 or above (ideally >1.5) is good stability; 1.0-1.4 is marginal stability; <1.0 is unstable.

“Most men … can seldom accept the simplest and most obvious truth if it … would oblige them to admit the falsity of conclusions … which they have woven, thread by thread, into the fabrics of their lives.”— Leo Tolstoy

Originally posted by fritz:swage -- did you order one of the JP barrels and receive the above notice?

I wonder if barrel twist rate has anything to do with the issue. I don't know if a 1:7 twist works for those 90 grain bullets; instinct tells me something a little faster might be better. Chamber dimensions might also come into play.

Fritz - I preordered an upper when they were announced. I've decided to give up my place in line on my build. The hype isn't living up to real world data. For now I'll stick with my Grendel.

That's reasonable. It seems cartridge designs that differ from the 223 case have their individual strengths and weaknesses. We must pick what works for own goals.

I've wondered if a 6.5 Grendel necked down to a 6.0 might be the ticket for long range shooting in an AR-15. I think one version is called a 6mm AR. If the velocity is high enough with a 105-107 grain high BC bullet, it might be interesting.

It's unfortunate that JP has some issues with their first barrels.

*****Sigfreund -- interesting data. I guessed it would take a 6.5 twist to stabilize the 90's.

I just wanted something different to tinker with. Knowing myself like I do, I'd get frustrated with it quickly and send it down the road. It wasn't worth it in the end with my desire to shoot the heavies.

The 6mm AR sounds interesting. I've already seen the 6.5 PRC necked down to 6 PRC locally. There are a lot of interesting wildcats being developed. I've opted for a 22 Creedmoor to satisfy my want for a flat shooting, fast .224. It'll be built on around a bolt action however. I think the .224 Valkyrie will do well on a bolt action as well. I know MPA already has a factory bolt action .224 they are offering.

As Sigfreund has mentioned, I think twist rates and barrel length will keep the .224 Valkyrie reaching it's full potential shooting the heavies on a gas gun platform. Time will tell and if anyone can figure it out, it's JP.

That's reasonable. It seems cartridge designs that differ from the 223 case have their individual strengths and weaknesses. We must pick what works for own goals.

I've wondered if a 6.5 Grendel necked down to a 6.0 might be the ticket for long range shooting in an AR-15. I think one version is called a 6mm AR. If the velocity is high enough with a 105-107 grain high BC bullet, it might be interesting.

It's unfortunate that JP has some issues with their first barrels.

*****Sigfreund -- interesting data. I guessed it would take a 6.5 twist to stabilize the 90's.